In LTE (Long Term Evolution) standardized in 3GPP (3rd Generation Partnership Project) which is a group aiming to standardize a cellular mobile communication system, SON (Self-Organizing Network) is applied in which a radio base station is able to change setting relating to a base station without using any manpower. As one type of the SON, there is an energy saving technology in which a base station reduces its own power consumption (refer to Non-Patent Literature 1).
Furthermore, in LTE, and LTE Advanced, which is a sophisticated version of LTE, there has been proposed a network configuration in which a base station (hereinafter, a small base station) having transmission power lower than that of a macro base station is added to a radio communication network including the macro base station. According to such a small base station, since it is possible to complement a communication area of the macro base station or distribute the traffic load of the macro base station, it is possible to improve service quality.